Register now for information about the Fourth Annual Forum.
At the 3rd annual event, some of transport's most highly-regarded speakers stimulated the audience with their views on how to deal with uncertainty in model applications.
Modellers urged to respond to new transport challenges
The modelling community needs to change the way it does things, the third annual LTT-sponsored Transport Modelling Forum heard last week, and for more than one reason. Stephen Joseph, executive director at the Campaign for Better Transport, for example, said that, in an increasingly 'carbon-constrained' world (due to the problem of 'peak oil' as well as climate change), past transport trends such as trip lengthening, car-based development and mode switch to motor vehicles could not and would not continue. Therefore, Joseph suggested, transport appraisal and modelling techniques based on past trends continuing will prove inadequate, "even if carbon is priced in".
Joseph predicted a world in which far greater priority will be given by government to 'smarter choices' and carbon emissions will be just as important a consideration as reducing congestion when considering traffic management measures such as speed limits and road user charging. Consequently, priority will increasingly be given by government to low carbon transport modes when managing traffic and parking. The whole thrust of the Government's road building programme will also change, he added, with more emphasis put on schemes that will help reduce carbon emissions, rather than increase them.
A brave new world?
"So what does all this mean for transport modelling?" he asked rhetorically. "We need modelling that can cope with measures such as carbon audits of major policy and location decisions (e.g. centralising schools, moving job centres, closing banks and post offices); and land use planning that reduces rather than increases the need to travel. Parking policy was key here because too much lowers densities, spreads cities and increases car dependence, Joseph said, noting also that modellers will need to take account of a reduced disparity between motoring costs and fares and action to reduce the growth in aviation.
In the question and answer session after Joseph's presentation at least one transport modeller, consultant Peter Davidson, agreed at least in part with the CBT's executive director's assertion that rising fuel prices will alter travel patterns irreparably. "For low cost airlines the… fuel costs will knacker them," was his typically forthright estimation of the future of aviation. And in response Joseph opined that "the days of stag weekends in Prague are over" but added that this could mean a significant increase to, for example, trips to historic towns within the UK.
Consultant Derek Halden's presentation to the Transport Modelling Forum focused on the need for changes in the relationship between modellers and transport planners. "Transport policy has moved on," he said. "We now start by asking what sort of places we want and how people's needs can be met. That is why transport is increasingly funded through cross-sectoral mechanisms such as Local Area Agreements with evidence of changes in access rather than just travel demand. However, the greatest problem is to close the gap between public understanding and transport policy and models could help to close these gaps - but need to work much harder as tools to deliver a dialogue between transport planners and users.
Halden of DHC suggested that, in order for transport models to become more relevant to transport decisions, there needed to be greater segmentation of travel markets, greater transparency of parameters and assumptions and a faster turnaround to respond to policy questions. He also warned that: "Transport policy implemented in isolation from other government policy is fairly unimportant for the future of transport." Expanding on this point, he observed that models that are sensitive mainly to transport infrastructure change can be useful for detailed infrastructure design but that policy and investment decisions need much better analysis of the most important impacts and sensitive factors, such as demographic changes or fuel price impacts. "The transport economy of the UK exceeds £200bn per year but transport modellers rarely provide the information needed by politicians on practical options to influence, regulate and manage these huge markets," Halden said.
The need to involve non-transport parameters in the modelling mix is not a new idea, of course. "My experiences of partnership studies at that time [1994] showed how to analyse changes outside transport," Halden said. "And that by doing so we could influence things like land use plans that would ultimately have a greater influence on travel demand than any changes to transport infrastructure or services. However, in the early 1990s we failed to deliver transport partnership projects using this analysis. Cross-departmental and cross-sectoral funding mechanisms were insufficiently developed and, as a result, policy models fell out of fashion - which is a pity". On a more optimistic note, however, Halden added that: "We now have a more conducive policy context where we make the connections. The social inclusion unit, Eddington, SACTRA and others have shown that analysis of accessibility (or connectivity if we want to use the language of a network provider) helps us to understand impacts on people and places."
The wave of the future?
"The [transport] analysis of the future has more user involvement," Halden opined. "In a safer routes to school scheme we draw maps with school children, discuss potential hazard locations with parents and negotiate solutions that local people want to use. I think we need to accelerate progress in providing Wiki interfaces for transport networks, learning lessons from gaming about user interfaces, and use these better within the modelling process."
Halden's consultancy manages national accessibility analysis work for the DfT and he has recommended to the Department that user interfaces with local communities should be developed to allow all partners to share and validate all inputs and outputs. "We also need to be able to factor in forecasts from demand models, perhaps with area-based relationships to represent forecast changes in supply and demand," he said. "The best way to manage uncertainty is to deliver the future," Halden concluded, returning to the main theme of his presentation. "This means including all factors in the analysis - not just the ones for which data are available. If a sensitive factor is the local health reorganisation plans then, rather than accepting uncertainty by ignoring these plans, a more rational approach is needed though partnership with the health service to jointly secure shared aims such as for better access. The modelling of the future will then hopefully plan better places for people.
David Nock, a project manager at the Highways Agency, used the Forum to echo some of Halden's comments and call for the modelling fraternity to change by making more of an effort to include the end-users at a far earlier stage of model development. "Why should people listen to modellers?" he asked, noting that, at present, clients often have only the haziest idea of what transport models can actually do for them. "Clients often ask if the model is DMRB (Design Manual for Roads and Bridges) compliant without really knowing what this means," he joked. Nock did have some sympathy for the modeller's plight, however, observing that: "The big problem is that decision makers want certainty - which models can't give them."
The Transport Modelling online resource is supported by:
